Modern industrial tissue-making machines operate at very high speed—up to 2,000 meters per minute. The basic layout of the “dry” side of a tissue-making machine is shown in U.S. Pat. No. 9,725,852, the contents of which are incorporated by reference in their entirety. The product of the initial stages of tissue-making is a so-called parent roll, a single-ply roll of tissue that can be quite large—1.3 to 2.7 meters (4.3 to 8.9 feet) in length and up to 3 meters (9.8 feet) in diameter.
Parent rolls are an intermediate product. Typically, they are subjected to further processing operations to produce a finished tissue or paper product. For example, a converting operation or a combining rewinder may be used to produce 2- or 3-ply tissue.
Occasionally, a finished parent roll may not meet quality standards, in which case the paper on it is reprocessed and recycled. The first step in this reprocessing of rejected parent rolls is removing the tissue from the roll, a process called slabing, so that the roll's core can be re-used. In the slabing process, a knife, water jet slitter, or other such tool is used to split the parent roll lengthwise, so that the slabs of tissue can be transferred to a hydro pulper for conversion into a set slurry pulp and sent back through the formation process. This process is laborious and, because of the heavy manual labor and the tools used, it can be dangerous. Muscle strains and cuts are quite common.
Similar issues arise when combining and converting re-winders are used. Parent rolls are sent to these winders and their internal cores are used to mount them on a winding stand. Once the paper or tissue on the parent roll is converted into a commercial product, some residue remains and must be removed from the core so that the core can be re-used. The same manual techniques and tools are used as earlier in the process, raising the same risks of injury.